1. Field of the Invention
The invention relates to a safety belt roll-up device having a U-shaped housing, i.e. a base plate with two parallel end walls extending therefrom, and a belt shaft with its free ends extending through holes in the two end walls and to a method for manufacturing such a safety belt roll-up device.
2. Description of the Prior Art
A U-shaped roll-up device housing made of sheet steel is used in known safety belt roll-up devices of this type. The side walls of the housing support the belt shaft and the belt reel. For this purpose, relatively large openings are provided in the side walls through which the free ends of the belt shaft extend and are supported freely rotatably in resilient bearings, for instance, laterally to the side walls. Supported on the belt shaft, secured against rotation, between the side walls is a special belt reel consisting, for instance, of plastic material with lateral reel flanges, the diameter of which is larger than that of the above-mentioned openings or holes in the side walls. Locking discs which are, for instance, serrated on both sides may be provided and likewise connected, secured against rotation, to the stable belt reel. The locking discs are located inside the holes and cooperate with a ratchet which releases automatically in case of danger such that the belt shaft and therefore, the belt reel is blocked immediately after the release. A flexible safety belt is wound on the belt reel. In assembling the safety belt roll-up device, the belt reel is first inserted between the mutually parallel side walls at the housing, whereupon the belt shaft is moved into its desired position axially through the holes and through a central hole in the belt reel. After the belt reel and the belt shaft are connected to each other secure against rotation, the belt reel of the belt shaft serves for axial security, i.e. prevents axial movement. As is customary, the belt shaft is connected with a rewinding spring on one side of the housing, while the release mechanism for the ratchet pawl is arranged on the other housing side. From the above it will be evident that the unit which carries and supports the safety belt requires two separately produced parts. Further the assembly of these parts, due to the necessity alone of feeding these parts, i.e. the belt shaft and the belt reel in different directions, is relatively complicated and expensive, and this does not include the parts or means which are required to connect the belt shaft and the belt reel to each other and make them secure against rotation relative to each other.